The index covering all import prices rose for the second time in the past 12 months. Over the past year, the index dropped 5.2 percent.

The September advance was led by a 2.6 percent increase in prices for imported petroleum, which had gained 1.7 percent in August. Despite the recent gains, petroleum prices fell 21.1 percent over the past 12 months.

Meanwhile, nonpetroleum import prices recorded no change in September, after declining for seven consecutive months. The index declined 2.6 percent over the year.